[PATCH 4/4] odd length data handling for __atapi_pio_bytes()

[Albert Lee <albertcc@tw.ibm.com>]

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Hi Jeff,

Problem:
- When odd length data is transfered, the last byte of data is lost.

Changes:
- When an odd length data transfer is seen, round it to the next even length.
   (The same as atapi_input_bytes() does in the ide-iops.)

Attached please find the patch against the linux-2.6.git tree for your review. Thanks.

Albert

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>

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--- 13_atapi_pio_trailing_data_handling/drivers/scsi/libata-core.c	2005-06-06 13:57:18.000000000 +0800
+++ 14_atapi_pio_odd_handling/drivers/scsi/libata-core.c	2005-06-06 14:54:36.000000000 +0800
@@ -2607,6 +2607,13 @@
 	/* don't cross page boundaries */
 	count = min(count, (unsigned int)PAGE_SIZE - offset);
 
+	/* handle the odd condition */
+	if (unlikely(count & 0x01)) {
+		DPRINTK("ata%u: odd count %u rounded: qc->nbytes %u, bytes %u\n",
+			ap->id, count, qc->nbytes, bytes);
+		count++;
+	}
+
 	buf = kmap(page) + offset;
 
 	qc->curbytes += count;